Data authentication

1. A first storage medium for carrying data content, comprising an electronically readable modification-resistant first identifier that distinguishes said medium from other storage media, and having stored thereon a digital signature associated with a data content portion carried by the storage medium, the digital signature including a combination of said first identifier, as read from said storage medium, and a second identifier that identifies a device that originated the digital signature prior to the digital signature being applied to the storage medium, whereby the first identifier and the digital signature can be used for verifying that the data content is stored on an authorised storage medium in an authorised manner.

2. The first storage medium according to claim 1 , wherein said digital signature is generated by encrypting a digest of a combination including the first and second identifier and at least some of the data content portions.

3. The first storage medium according to claim 1 , wherein the data content is recorded onto the storage medium without modification of the form and/or content of the data content.

4. The first storage medium according to claim 1 , having stored thereon a plurality of said data content portions and a plurality of corresponding respective said digital signatures.

5. The first storage medium according to claim 1 , wherein the first identifier is copy-resistant by commonly available consumer rewriters.

6. The first storage medium according to claim 1 , wherein the digital signature is stored on the storage medium accompanied by a time-stamp.

7. The first storage medium according to claim 1 , wherein said digital signature is encryption of a digest of a combination of the first identifier, at least some of the data content portion, and the second identifier.

8. The first storage medium according to claim 1 , wherein the first and second identifiers are unencrypted on a write-once read-many portion of the storage medium.

9. A method of verifying that data content is stored on an authorised first storage medium in an authorised manner, the first storage medium bearing an electronically readable modification resistant first identifier that distinguishes said medium from other storage media, comprising generating a digital signature associated with a data content portion by reading the first identifier from the storage medium and encrypting a digest of a combination of the first identifier, the data content portion, and a second identifier that identifies a device that originated the digital signature prior to the digital signal being applied to the storage medium, storing the resulting digital signature and the data content portion on the storage medium, and using the combined identifier and the digital signature to detect unauthorised modification of data on the first storage medium.

10. A method of authenticating data stored on the first storage medium according to claim 2 , comprising: i) searching a data storage medium for the digital signature; ii) responding to the digital signature to obtain a digest including a combination of the data content and the first and second identifiers; iii) reading the Identifier from the storage medium and generating a digest using the data content and the identifier; iv) comparing the digests; and v) executing an action in relation to the data stored on the medium if the digital signature is not found or if the digests do not correspond to one another.

11. A method according to claim 10 , wherein the action includes denying or restricting access to the data content stored on the medium, and/or creating a message for display to a user of the medium.

12. A data writer and/or reader adapted to carry out the method of claim 10 .

13. A data storage device comprising a data writer and/or reader according to claim 12 .

14. A first storage medium carrying data content, comprising an electronically readable modification-resistant first identifier that distinguishes said medium from other storage media, and having stored thereon a digital signature associated with a data content portion carried by the storage medium, the digital signature including encryption of the first identifier and a second identifier that identifies a device that originated the digital signature prior to the digital signature being applied to the storage medium and at least some of the data content portion, whereby the combined identifier and the digital signature can be used for verifying that the data content is stored on an authorised storage medium in an authorised manner, and wherein the data content is recorded onto the storage medium without modification of the form and/or content of the data content.

15. A storage medium carrying data content, comprising an electronically readable modification-resistant identifier for distinguishing said medium from other storage media, and having stored thereon a digital signature associated with a data content portion carried by the storage medium, the digital signature having been generated using said identifier, read from said storage medium, whereby the identifier and the digital signature can be used for verifying that the data content is stored on an authorised storage medium in an authorised manner, wherein said digital signature is generated by encrypting a digest of a combination including the identifier and at least some of the data content portion, and wherein the data content is recorded onto the storage medium without modification of the form and/or content of the data content, and wherein said digital signature is generated by encrypting (a) a digest of a combination of the identifier, (b) at least some of the data content portion, and a device identifier for identifying a device which effects generation and/or storage of the digital signature prior to the digital signature being applied to the storage medium.

16. A method of detecting the use of a data storage medium carrying illicitly copied data, wherein (a) the medium on which the data are stored has, a unique first identifier assigned to it, (b) a digital signature including the first identifier and a second identifier that identifies a device and/or a second storage medium that originated the digital signature prior to the digital signal being applied to the storage medium, the identifier being recorded on a non-copyable portion of the medium, and (c) a data segment corresponding to the combined identifier is appended to data stored on the medium; comprising the steps of: searching the medium for the data segment and the digital signature; and notifying a third party if upon comparison, the identifier on the non-copyable portion, when combined with a predetermined combination of bits, does not correspond with the digital signature on the data segment.

17. A method of verifying that data content has been stored in accordance with claim 9 on an authorized storage medium in an authorized manner, comprising using the first and second identifiers and the digital signature to detect unauthorized modification of data on the first storage medium.

18. A method of: (a) preventing reading of first body data of interest to a user by a commonly available consumer reader of commonly available consumer storage media, the first body data having been illicitly written on a major portion of a first commonly available consumer storage medium as a result of the first body data being illicitly copied from a second commonly available consumer storage medium by a commonly available consumer rewriter from the second storage medium to the first storage medium, and (b) authorizing reading of second body data of interest to a user by a commonly available consumer reader of commonly available consumer storage media, the second body data having been properly written on a third commonly available consumer storage medium, each of said storage media being of the same general type and including a read only portion, the method comprising: writing first data uniquely associated with the third storage medium on the major portion of the third storage medium, the first data being derived by combining identifications of the third storage medium and a device that applied the second body data to the third storage medium; writing a unique identifier of the third, storage medium on a non-copyable portion of the third storage medium; writing second data uniquely associated with the second storage medium on the major portion of the second storage medium, the second data being derived by combining identifications of the second storage medium and a device that applied the first body data to the second storage medium; writing a unique identifier of the second storage medium on a non-copyable portion of the second storage medium; arranging the commonly available consumer rewriter so the commonly available consumer rewriter can rewrite body data onto the major portion of any of the commonly available storage media, but can not rewrite information on non-copyable portions of the commonly available consumer storage media onto any of the commonly available storage media; and arranging the commonly available consumer reader so the commonly available consumer reader (a) can read the body data on the main portion of the third storage medium as a result of the commonly available consumer reader being able to match signals resulting from the first data in the major portion of the third medium and the unique identifier on the non-copyable portion of the third medium, and (b) can not read the body data on the first storage medium because of the inability to derive signals that match in response to data in the major portion of the first medium with the identifier in the non-copyable portion of the first medium.

19. The method of claim 18 wherein the commonly available consumer storage media are any one of CDs, tapes, magnetic-optical disks, DVDs, magnetic disks and ROMs.

20. An arrangement for: (a) preventing reading of first body data of interest to a user by a commonly available consumer reader of commonly available consumer storage media, the first body data having been illicitly written on a major portion of a first commonly available consumer storage medium as a result of the first body data being illicitly copied from a second commonly available consumer storage medium to the first storage medium by a commonly available consumer rewriter, and (b) authorizing reading of second body data of interest to a user by a commonly available consumer reader of commonly available consumer storage media, the second body data having been properly written on a third commonly available consumer storage medium, each of said storage media being of the same general type and including a read only portion, the arrangement comprising: first data uniquely associated with the second storage medium on the major portion of the second storage medium, the first data resulting from a combination of identifications for the second storage medium and a device that applied the first body data to the second storage medium; second data uniquely associated with the third storage medium on the major portion of the third storage medium, the second data resulting from a combination of identifications for the third storage medium and a device that applied the second body data to the third storage medium; the first storage medium not including on the major portion thereof the first data; the commonly available consumer rewriter being arranged so the commonly available consumer rewriter can not rewrite, onto any of the storage media, information on the non-copyable portion of any of the storage media; the commonly available consumer reader being arranged so it can (a) read the body data of a commonly available consumer storage medium that the commonly available consumer reader is reading as a result of the commonly available consumer storage medium that the commonly available consumer reader is reading including on the major portions thereof data uniquely associated with that storage medium that can be matched with the identifier on that storage medium, and (b) can not read the body data of a commonly available consumer storage medium that the commonly available consumer reader is reading in response to the commonly available consumer storage medium that the commonly available consumer reader is reading as a result of the commonly available consumer storage medium that the commonly available consumer reader is reading including on the major portions thereof data uniquely associated with that storage medium that can not be matched with the identifier on that storage medium; and whereby the commonly available consumer reader can read the second body data on the third storage medium to a user and can not read the first body data on the first storage medium to a user.

21. The arrangement of claim 20 wherein the commonly available consumer storage media are any of CDs, tapes, magnetic-optical disks, DVDs, magnetic disks and ROMs.